1. Field of the Invention
The present invention relates to a LCD projector and, more particularly to a horizontal/vertical dual-mode LCD projector, which comprises a first casing holding two lens arrays and a lamp module, and a second casing holding an optical module and connectable to the first casing in such a manner that the first casing can be turned relative to the second casing through 90xc2x0 angle.
2. Description of the Related Art
Conventional LCD projectors have two types, namely, the horizontal LCD projectors for use in a horizontal position and the vertical LCD projectors for use in a vertical position. These conventional LCD projectors have a limitation in use, i.e., a horizontal LCD projector cannot be used in a vertical position, and a vertical LCD projector cannot be used in a horizontal position.
FIGS. 1 and 2 show a horizontal LCD projector according to the prior art. According to this design, the horizontal LCD projector comprises an integrated housing 10a, which houses a lamp module 20a, two lens arrays 22a, and an optical module 30a. The optical module 30a comprises an optical lens set 31a, three video modulators 32a, and a projection lens 33a. The light of the lamp bulb 21a of the lamp module 20a passes through the lens arrays 22a to the optical lens set 31a and the video modulators 32a, and then the projection lens 33a projects the image of the light onto a screen or the like. The lens arrays 22a and the video modulators 32a have a respective particular length to width ratio, for example, 4:3; 16:9; 15:9. When mounting the lens arrays 22a and the video modulators 32a in the housing 10a, the lengths and widths of the video modulators 32a must be respectively corresponded to the lengths and widths the lens arrays 22a. There is also provided a cover installed in the top side of the LCD projector and a driving circuit board located on the top of the cover (not shown) for controlling the operation of the horizontal LCD projector.
The aforesaid horizontal LCD projector is still not satisfactory in function because of the following drawbacks.
1. When set the horizontal LCD projector in vertical due to a space limitation, the phase of the projected image is 90xc2x0 biased from the original image phase, not suitable for viewing.
2. When set the horizontal LCD projector in vertical, the array lens 22a cannot easily be rotated through 90xc2x0 to match the 90xc2x0 biased video modulators 32a. 
3. The video modulators 32a each have a lead wire contact 34a at one long side (see FIG. 3) or one short side (see FIG. 4). The video modulator having the lead wire contact at one long side (see FIG. 3) is suitable for use in a horizontal LCD projector because it is in proximity to the driving circuit board when installed in the housing of the horizontal LCD projector. The video modulator having the lead wire contact at one short side (see FIG. 4) is not suitable for use in a horizontal LCD projector because it is disposed at 90xc2x0 angle biased from the driving circuit board when installed in the housing of the horizontal LCD projector.
Therefore, it is desirable to provide a horizontal/vertical dual-mode LCD projector that eliminates the aforesaid drawbacks.
The present invention has been accomplished under the circumstances in view. It is the main object of the present invention to provide a horizontal/vertical dual-mode LCD projector, which can be alternatively set between the horizontal operation mode and the vertical operation mode. It is the second object of the present invention to provide a horizontal/vertical dual-mode LCD projector, which has its first casing and its second casing adjustably connected together to fit the horizontal or vertical operation mode, keeping the long sides and short sides of the lens arrays in the first casing corresponded to the long sides and short sides of the video modulators of the optical module in the second casing respectively. It is the third object of the present invention to provide a horizontal/vertical dual-mode LCD projector, which fits different models of video modulators, for enabling the lead wire contacts of the loaded video modulators to be set close to the driving circuit board for quick connection.
To achieve these and other objects of the present invention, the horizontal/vertical dual-mode LCD projector comprises a first casing, the first casing having a square mounting open side; a second casing, the second casing having a square mounting open side connectable to the mounting open side of the first casing between two positions at 90xc2x0 angle; a lamp module mounted in the first casing; at least one lens array respectively mounted in between the mounting open side of the first casing and the lamp module; and an optical module mounted inside the second casing.